Method of applying coatings to rubber, balata, and like articles, and articles produced thereby



Patented. Apr. 4, 1939 UNITED ST ES PATENT orr cs rm-rnon or cosmos ro- I.

- RUBBER, BAIATA,

AND LIKE ARTICLES.

AND aa'ncms raonucsn mannr Robert J. snelling ltochcster, Pa, assignor to impervious Varnish Company, Pittsburgh, Pa, a corporation of Pennsylvania No Drawing. A pplication lune 8, 1,936, I

' Serial No. 84,156

lmaim.

This invention relates to the art of applying coatings of paint, lacquer, varnish, enamel and like protective or ornamental coatings forrubber,

balata and like articles, such as golf balls, hot

I water bottles, etc.

' Heretofore, in the art of painting, varnishing,

lacquering, enameling or similarly applying coatingsto rubber, balata and like articles, much difliculty has been experienced in obtaining a coating 10 which willadhere to the surfaces of the articles, and not peel, split, chechcrack or discolor upon aging and in use of the articles. This, it has been discovered by the present inventor, has been due to the character of the surfaces of the article due u to the compounds used, and particularly to the presence of certain substances on the finished articles and changes in the surface substances thereof during aging. Such objectionable surface materials may be produced by oxidation, y blooming of sul hur from articles vulcanized by the use ofthis material, continued vulcanization articles the changes which oxidation or further vulcanization produce and change the character of the surfaces of the articles before the coating is applied and probably also microscopically etch the surfaces of. the articles to provide a mechani cal interlock between the article and its coating.

This treatment has been found to produce highly saflsfactory results even in articles such w golf balls, which are subjected to severe treatment in use, the coatings applied to balls pretreatedas 5 provided herein adhering tenaciously. without checking, cracking, diseoloring, etc. V

To carryout the invention, the'artieles, after l they have been-inoldedor vulcanized toshape, are

5 treated with an oxidizing agent such as potas- 50 slum permanganate, hydrogen peroxide, etc., and

preferably also a halogenizing agent such as chlorine, bromine, etc., or derivatives thereof.

For example, 'a highly satisfactory surface pretreating process may be carried out by subjecting the surfaces of the articles to the action of 5 Parts by weight mm 4 5 HC 3 mo 85 Golf balls, with balata covers or vulcanized rubber balls, etc., after being'shaped or'vulcanized, may be immersed in the above solution in a porcelain or glass container for five minutes, or so.

Thereafter the balls may be removed and rinsed until the rinsing water ceases to be discolored, whereupon the balls may be bleached white by being tumbled in a saturated solution of oxalic '.acid. The balls arethen washed thoroughly in clean water, removed to drying trays and dried atroom temperature. Lower priced balls may be sprayed two full coats (approximately twenty minutes between coats) with a mixcomprising fifty percent (50%) lacquers and fifty percent (50%) reducer or thinner. Better grade balls may be given three coats (approximately twenty:

minutes between coats) consisting of forty percent (40 lacquer and sixty percent (60%) It has been found that by the improved process the materials at the surfaces of articles of rubber, balata or the like, are so changed as not to interfere with the normal drying of the coatings, which dry quickly without checking or cracking. It will'be understood that theforegoins treatment changes the materialsof the rubber articles. to end-products of ageingbut only at the surface thereof and the elasticity, resilience or life of the body of the article is substantially unaffected.-

The terms oxidiz'ing" or oxidizing agen as used herein are not intended to cover other than true oxidimtion, i. e.,'such changesas are brought about, 'by treatment with a" material which supplies oxygen in' a state or condition to attack the surface materials of the rubber articles to produce the desired end-products on the surface' of the articles prior to'painting. c c As an example of other oxidizingagents, hydrogen peroxide (concentrated) may be successfully used. Also sodium bichromate (NaaCraOw).

Chlorine or bromine solutions may be used as the v halogenizing reagent.

The pre-treatment of the articles or balata,

ties of the paint, lacquer, varnish or enamel used;

-Modiflcations of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claim.

What is claimed is: h That method for applying paint, varnish, lacquer, enamel or the like to rubberibaiatapr the warm I.

like which comprises pretrea'tlngthe surraces of the articles for a comparatively short period with an oxidizing agent comprising permanganate to produce at the surfaces only of the articles products resulting from substantially -5" complete oxidation or the materials at the sur faces of such articles without substantially aflecting the physical properties. including the life. elasticity or resilience or the body 01 the article.

said suriace being etched and non-glossy from 10 action of the "oxidizing agent, and thereafter applying the paint,--varnish or enamel or the like tothe treated surfaces of said articles.

aonnn'r J. surname. s 

